Rubber paving block



Oct. 20, 1936. w. PIPES RUBBER PAVING BLOCK Filed May 15, 1931.

Patented 1 Oct. 20, 1936 atsms PATENT OFFlCE 2.057.738 RUBBER PAVINGanocx Walter L. Pipes, Elizabeth, N. 5., asslgnor, by mesne assignments.to United States Rubber Company, New York, N. Y., a corporation of NewJersey Application May 15, 1931; Serial No. 537,515

2 Claims.

My invention relates to paving blocks and more especially to pavingblocks laid on a wet or plastic base which hardens in engagementtherewith. v

In applying paving blocks to a wet or plastic base, an example of whichis concrete or mortar, one methodis to provide small blocks withprojections on their lower surfaces which are forced into the wet orplastic base to serve as anchors 10 for the blocks when the basehardens. The projections are frequently provided with enlarged heads toincrease the anchorage available. Such blocks must be laid closelytogether to avoid cracks in the exposed wearing surface. Care l must betaken to insure that the base material fills in the spaces behind theenlarged heads, which requires, a uniform tamping of the block dimcultto obtain with unskilled labor.

The trapping of air between the surface of the 20 base and theundersurfaces of the blocks also tends to cause a floating or moving ofthe blocks out of close contact as they are tamped. The provision ofenlarged heads on the projections also adds to the difllculties ofmanufacturing 25 such blocks, which is usually done by molding, as thewithdrawal of the enlarged heads from the molds presents difliculties.

I provide a paving block overcoming many of the foregoing problems byproviding the lower 30 surfaces of the blocks with sloping projectionsof substantially uniform cross-sectional areas, and also by providinggrooves or ducts for the escape of trapped air, the blocks arepreferably of rubber with the projections integral therewith,

35 although it is to be understood that the invention is not limited torubber as various features of the invention may be utilized inconnection with other' paving materials. Preferably the projectionsdiverge outwardly, but I do not intend 40 to limit the invention in thisrespect.

The accompanying drawing illustrates a present preferred embodiment ofthe invention in which:

Fig. 1 is an inverted plan view of a paving 5. block embodying myinvention,

Fig, 2 is a transverse view of the block taken along the section line2-2 of Fig. 1 and illustrating the manner of embedding it in a base,

Fig. 3 is an inverted plan view of a paved area 50 showing a pluralityof blocks in engagement; and

Fig. 4 is a transverse view similar to Fig. 2 of a modified form ofblock.

Referring to the drawing, a paving block I, illustrated in the shape ofa hexagon, is provided 55 on its lower surface with a plurality ofangularly disposed projections 2. The projections 2 are of substantiallyuniform cross-sectional areas throughout their lengths. They preferablydiverge outwardly but it is to be understood that the invention is notlimited to such outward di- 5 vergence of the projections as they mayconverge inwardly or outwardly as desired. The projections 2 arepreferably integral with the body of the block I, but may be attached byother means such as cementing, curing and the like. The undersurface ofeach block is provided with one or more grooves 3 to permit the escapeof entrapped air when the block is laid on a wet or plastic surface.These grooves are relatively narrow as distinguished from anchoringgrooves formed in some blocks for receiving embedded keys or anchors ofthe hardened plastic material.

While the paving block I and the projections 2 are illustrated as beingof rubber, it is to be understood that other paving materials may beused in lieu of rubber.

As illustrated in Fig. 2, each block I is laid on the surface of a base4, and the projections 2 driven or tamped thereinto while the base 4,preferably concrete or mortar, is wet or plastic.

' The base 4 may be of any well known bituminous or hydraulic cementcomposition. Owing to the absence of enlarged heads on the projections 2the base material flows around them and between them and the innersurface of the block. The provision of the grooves 3 permits the escapeof air, thereby removing the tendency of such blocks to float or creepout of close engagement with each other. Some of the base material maywork into the grooves 3 and thereby assist the projections 2 inpreventing lateral displacement .of the blocks. Also, due to the broadbearing area, provided between the projections and grooves, the blockswill be firmly seated on the base 4, since the grooves 3 function mainlyto prevent the entrapment of air between said base 4 and the broadbearing areas of the block. In the modification of Fig. 4 the block IDhas projections l2 which are illustrated as extending downwardly andconverging inwardly from the 5 corners of the block into a hardenedconcrete or mortar base l4. By forming the projections l2 at the cornersand inclining them to the vertical the block I0 offers great resistanceto any upheaving forces and especially those forces tending to lift ortilt the block along its edge. The particular direction in which theprojections l2 incline to the vertical or to each other is not materialso long as the directions are so balanaced that the block has notendency to slide to one side he understood that it may be otherwiseembodied within the spirit of the invention and the scope of. theappended claims.

Having thus described my invention. what I claim and desire to protectby Letters Patent is 1. A paving block having a body outline of apattern to snugly engage similar blocks around its entire periphery tocompletely cover a wet concrete base, and separated angularly disposedanchoring projections of substantially uniform cross section throughouttheir lengths extending from the underface of said body for insertioninto and embedment in the concrete base, the number and arrangement ofthe projections being suchas to provide substantially equal "or balancedanchorage for said block in all directions, said projections throughoutat least most of their lengths being spaced from and terminating with inthe projections of the edges of the body to prevent the formation ofpockets in the concrete adjacent to said projections, the inner surfaceof saidbody. being provided with relatively narrow, radialventinggrooves extending outwardly between the projections to the edgesof the body whereby when the block is placed on wet concrete theentrapped air may escape during-the insertion of the projections block..I

2. A rubber paving block having a body outline of la" pattern to snuglyengage similar blocks around its entire periphery 'to completely cover awet concrete base, and separated angularly disposed anchoringprojections of substantially uniform cross section throughouttheirlengths extending from the underface of said body for insertion into anembedmentin the concrete base. the number and arrangement ofthe'projeeticns being such as to provide substantially equal or balancedanchorage for said block in all directions, said projections throughoutat least most of their lengths being spaced from and terminating withinthe projections of the edges of the body to prevent the formation ofpockets in the concrete adjacent to said projections, the inner surfaceof said body belng provided with relatively narrow, radial ventinggrooves extending outwardly between the projections to the edges of thebody whereby when the block is placed on wet concrete the entrapped airmay escape during the insertion of the projections without floating ofthe block.

without floating oi the

